[KleinMoretti]

Hello,everyone!
I have read《SU2-NEMO: An Open-Source Framework for High-Mach Nonequilibrium Multi-Species Flows》 and would like to try to reproduce some simple examples.

The first is the zero dimensionnal thermalbath using N2 gas model. I tried to solve it with NEMO EULER, but I found a strange problem.

The result about Tve and Ttr is very similar to the picture in the article，but the N2 massfraction is a little higher than the convergence value in the article. My N2 massfraction convergence value is 0.7787, while the convergence value in the article is around 0.65.

The calculation of Tve and Ttr is related to the source term in the eve equation, the source term in the eve equation is related to wdot1 and wdot2. So the mass fraction and the temperature should be coupled together? Why is the temperature correct but the mass fraction wrong?

Thank you in advance for your time and consideration. I truly appreciate any insights or advice you may have to offer.

[wallym]

Hiya!

Thanks for using SU2-NEMO and posting your question here!

You are correct that there is a coupling between the chemistry and thermal nonequilibrium terms. Would you mind posting your configuration file? I can take a look to see if I can find anything.
Do you have the FROZEN_MIXTURE option as YES?

I hope this helps,
Wally

[KleinMoretti]

Originally Posted by wallym

Hiya!

Thanks for using SU2-NEMO and posting your question here!

You are correct that there is a coupling between the chemistry and thermal nonequilibrium terms. Would you mind posting your configuration file? I can take a look to see if I can find anything.

A N2 concentration of 0.7787 is nearly atmospheric which definitely shouldn't be the case if you are ending with a temperature of nearly 7500K. Do you have the FROZEN_MIXTURE option as YES?

I hope this helps,
Wally

Hello wallym, thank you very much for your reply.
As you said, I didn't set FROZEN_MIXTURE=YES. I just tried to set it to YES,then N2 massfrac is always 1 and N massfrac is always 0, and the convergence temperature becomes about 14000K.

[KleinMoretti]

Thank you again for your kind reply!This is my config file.

[wallym]

Awesome, it looks like your config is set up properly - and matches the case file that I have.

Ahh, sorry. The plots you are referencing include molar fraction, not mass fraction. If you convert to mole fraction, your results should match up.

Let me know how those compare.

Wally

[KleinMoretti]

Originally Posted by wallym

Awesome, it looks like your config is set up properly - and matches the case file that I have.

Ahh, sorry. The plots you are referencing include molar fraction, not mass fraction. If you convert to mole fraction, your results should match up.

Let me know how those compare.

Wally

It was so careless of me.Thank you very very much for your help! Now the result is correct！